Editor: Antoine Guisan
Interspecific differences in tree growth and mortality responses to environmental drivers determine potential species distributional limits in Iberian forests
Article first published online: 27 MAY 2013
© 2013 John Wiley & Sons Ltd
Global Ecology and Biogeography
Volume 22, Issue 10, pages 1141–1151, October 2013
How to Cite
Benito-Garzón, M., Ruiz-Benito, P. and Zavala, M. A. (2013), Interspecific differences in tree growth and mortality responses to environmental drivers determine potential species distributional limits in Iberian forests. Global Ecology and Biogeography, 22: 1141–1151. doi: 10.1111/geb.12075
- Issue published online: 4 SEP 2013
- Article first published online: 27 MAY 2013
- MCI. Grant Number: INTERBOS3-CGL2008-04503-C03-03
- INIA. Grant Number: SUM2008-00004-C03.01
- a Juan de la Cierva postdoctoral fellowship
- a FPU fellowship from the Spanish MEC. Grant Number: AP2008-01325
- Climate change;
- demographic rates;
- National Forest Inventory;
- phenotypic variability;
- species distributional models;
- tree growth;
- tree mortality
Tree growth may be enhanced by carbon dioxide fertilization unless drought stress becomes too severe, yet the likely increase in tree growth under a warmer climate is still controversial. Tree mortality has increased in some regions, but its multifactorial nature makes the prediction of likely global trends difficult. The aims of this work are: (1) to assess which abiotic, structural and competition factors influence tree growth and tree mortality in mainland Spain, and (2) to evaluate whether these processes would drive species distributions and would improve current niche model predictions.
We projected species distributional models by integrating nonparametric tree growth and tree mortality models based on repeated surveys of diameter at breast height and mortality for 40,721 trees distributed in 45,301 plots, which include the 11 most common canopy tree species in continental Spain, as measured in the second and third National Forest Inventories, with a mean lag time of 11 years.
Tree growth and tree mortality were explained by an assemblage of many factors, among which climate and competition played a key role. The accuracy of models including tree growth and tree mortality in predicting tree habitat suitability was comparable to classical niche models based on species occurrence. Projections under climate change showed for 9 out of 11 species, a likely increase in tree growth that would be counteracted by an increase in tree mortality, suggesting that even if growth rates increase, mortality would limit the species ranges under global warming expectations.
Growth and mortality are major determinants of species distributions. Under future climate change expectations, our model suggests that growth may increase for some Iberian species, but even in this case, species ranges at the rear edge would be limited by an increase in mortality rates.